i had a problem for awhile with (for lack of a better explanation) a stutter between 40 and 60mph in drive and overdrive. thought i was the torque conv. or maybe the rearend but as it turns out it was a vacuum hose on the EGR valve pressure sensor. hose was soft at the end and worn out. replaced it and havent had the problem since. i looked all over this site to help solve this problem and no luck. hope this helps someone.